fix(snowflake): generate LIMIT when OFFSET exists #4575 (#4581)

* fix(snowflake): generate LIMIT when OFFSET exists

* PR feedback 1

Co-authored-by: Jo <[email protected]>

* PR feedback 1 (change snowflake test)

---------

Co-authored-by: Jo <[email protected]>

Author: geooo109

sqlglot/dialects/snowflake.py

@@ -1224,3 +1224,10 @@ def datesub_sql(self, expression: exp.DateSub) -> str:
                 self.unsupported("DateSub cannot be transpiled if the subtracted count is unknown")
 
             return date_delta_sql("DATEADD")(self, expression)
+
+        def select_sql(self, expression: exp.Select) -> str:
+            limit = expression.args.get("limit")
+            offset = expression.args.get("offset")
+            if offset and not limit:
+                expression.limit(exp.Null(), copy=False)
+            return super().select_sql(expression)

tests/dialects/test_snowflake.py

@@ -2360,3 +2360,11 @@ def test_window_function_arg(self):
         self.assertEqual(ast.sql("snowflake"), query)
         self.assertEqual(len(list(ast.find_all(exp.Column))), 1)
         self.assertEqual(window.this.sql("snowflake"), "db.schema.FUNC(a)")
+
+    def test_offset_without_limit(self):
+        self.validate_all(
+            "SELECT 1 ORDER BY 1 LIMIT NULL OFFSET 0",
+            read={
+                "trino": "SELECT 1 ORDER BY 1 OFFSET 0",
+            },
+        )